Switch out the hashing implementation from MD5 to implementations such as adler128 and murmur3_128 (but certainly not limited to) and do some profiling to compare the net improvement on latencies and CPU usage

As we can't switch the algorithm from MD5 without breaking things, we could rev the MessagingService protocol version – like we already do for things like switching from Snappy compression -> LZ4, we could switch to the new hashing implementation once all peers in the node are upgraded and support the new MessagingService version.